Are my muscles weak?

May 18, 2021 - Amit Sachdev, MD, MS

Muscle strength and endurance decline with age. It is very common to wonder if your decline is more significant than expected. The short answer is that each person defines the strength and endurance that they desire. If you are not where you want to be, there are a few scenarios where this doctor would suggest that seeing a physician might be helpful.

The Basics: Strength is often measured by lifting or grip. Endurance reflects how long you can stay on task. Muscles rely on the basics: good blood flow, robust nutrients, oxygen and time to rest and recover. Muscles are controlled by the brain using a network of nerves. A skilled physician will tease out the cause of muscle dysfunction. A skilled patient will identify when something doesn’t feel right and attempt to explain what is not working well. 

Scenario #1: A notable decline in power that got worse quickly over a short period of time (0-6 months)

Weakness is classified by body region (see TABLE 1). Trying to be specific about what is weak and when weakness affects function can be very helpful. The hand is a great example. Patients often report arm weakness, when they really mean that the hand doesn’t work well. Weakness of the hand could present as a weak grip or clumsy coordination. A change in function that interferes with daily activities should result in a doctor visit. The symptoms in Table 1 are not just normal aging. Often these are issues that can be stopped or treated. The most important task is to identify the body region and the situations where something did not work correctly. The clinical history (that is, talking to the patient) provides significant insight in these situations.

Scenario #2: A decline in endurance that got worse over several years

These situations can be challenging to recognize and diagnose as they often evolve slowly over a few years. A classic example would be an older aged woman who enjoys walking the boardwalk in a beach town. She may return to that boardwalk two or three years in a row. She may only recognize a problem when she finds the need to sit down more frequently. A decline like this is not normal aging. In this scenario, it is most likely that the muscle is not getting what it needs to maintain prolonged activity. With daily activities there is often not a problem. With prolonged activity, issues become more obvious. Table 2 provides examples. Often, we need testing to understand the issue.

Concerns about strength and endurance are common and should first be brought up with a trusted primary care provider. Providing examples helps home in on the problem.

About the expert: Dr. Sachdev is a fellowship trained neuromuscular neurologist who practices at MSU. His practice focuses on the neck down neurologic issues. He has over 400 patients with rare muscle and nerve diseases, runs clinical trials, teaches, and is routinely interviewed nationally.

TABLE 1 – Presentations of loss of strength in select body regions

Body Region	Common Presentations of Weakness	Examples of Diseases
Eyes	Drooping	Levator Dehiscence
Eyes	Double Vision	Stroke of the third cranial nerve
Mouth	Coughing/Gagging	Achalasia
Neck	Decreased range of motion	Cervical spine disease
Shoulder girdle	Unable to raise arms	Polymyositis
Hand	Dropping Objects	Carpal tunnel syndrome
Chest wall	Shortness of Breath	Obesity Hypoventilation
Hip girdle	Unable to rise from a chair	Myasthenia Gravis
Ankle	Foot drop	Lumbar Level 5 Radiculopathy
Toes	Hammer toes	Peripheral Polyneuropathy
Half the body	Weakness in face, arm and leg	Stroke

 

TABLE 2 – Basic needs of the muscle and some scenarios where the body cannot meet those needs

Need	Examples Where Need Is Not Met
Oxygen	Asthma/ Lung Disease
Blood Flow	Heart Failure or Claudication
Nutrients	Vitamin B12 deficiency
Metabolism	Low Thyroid
A supportive environment	Chronic inflammation such as Hepatitis C or uncontrolled autoimmune diseases
Good connections to the brain	Central canal stenosis of the spine or myasthenia gravis